Please note I have not gone on my Timeless Vietnam tour with G Adventures yet. I booked it several months ago and will be going this December.
Be careful and proactively check your flight status online, because it might change and they won't bother to tell you about it. Our friend booked the same tour for the same date as us and noticed three days ago that the departure flight date had changed to one day earlier. I called their customer service today to verify, and they confirmed that yes, it had changed.
I didn't receive an email, phone call, or any notification of this change. What if I couldn't accommodate the flight change with my schedule and found out too late on my own, had I not checked? The customer service agent said that their flight agents don't work on the weekend and I would have received an email notification on Monday, but I don't buy that, since my friend checked three days ago on a THURSDAY. And if that truly is how they function, they should change and have these "flight agents" available over the weekend as well, because people in society don't just travel on weekdays.
Wish they notified us of this important trip change.